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1.
The conditions for cryopreservation of CD34+ hematopoietic stem cells (HSC) from umbilical cord blood (UCB) were optimized with a new cryo-medium containing 10% ethylene glycol (EG) and 2% dimethyl sulfoxide (Me2SO) using a controlled-rate freezing (CRF) method. After the cryopreservation of mononuclear cells (MNC) from UCB, recoveries of MNC, CD34+ cells, and total colony-forming units (CFU) were significantly improved compared to those in the control cryo-medium containing 10% Me2SO and 2% Dextran-40 (P < 0.05). This study shows that the new cryo-medium and CRF method provide better recoveries of MNC, HSC and total CFU than the control cryo-medium and isopropylalcohol freezing (IPA) method. Therefore, this cryo-medium, combined with the CRF method, is valuable for optimizing cryopreservation conditions for HSC from UCB to obtain satisfactory HSC recovery.  相似文献   

2.

Background

Though mass spectrometry (MS) assays are increasingly used for routine clinical measurements of serum total testosterone (TT), information about the variability of results is limited. This study assessed the variability of TT measurement results from routine MS assays.

Methods

Twenty serum samples (12 females, 8 males) were analyzed on 2 days by seven high performance liquid chromatography (HPLC), and one gas chromatography (GC)-tandem mass spectrometry (HPLC-MS/MS, GC-MS/MS) assays. Two samples (male and female) were provided in five replicates to assess the within-run variability. Results were compared against those obtained at National Institute of Standards and Technology (NIST). The within- and between-laboratory variability was assessed for each sample. Comparisons to the NIST results were performed using bias plot and Deming regression analysis.

Results

The overall coefficient of variation of the results obtained with MS assays was <15%CV at >1.53 nmol/L and <34%CV at 0.3 nmol/L. The between-assay variability was the major contributor to the overall variability. The assay precision was the highest (<3%CV) with assays using liquid-liquid extraction for sample preparation or GC-MS/MS. The mean percent difference to the reference assay was 11%. The slopes of Deming regression analysis of the MS assays were between 0.903 and 1.138 (correlation coefficient: >0.996). TT concentrations for one assay were above the measurement range.

Conclusions

The variability of TT measurement results among MS assays is substantially smaller than that reported for immunoassays. The type of sample preparation may affect assay precision. Standardizing assays can further reduce the variability of measurement results.  相似文献   

3.
4.

Background

The benefit of carbon monoxide as applied by controlled, continuous gaseous persufflation during liver preservation on postischemic graft recovery was investigated in an isolated rat liver model.

Methods

Livers from male Wistar rats were retrieved 30 min after cardiac arrest of the donor and subjected to 18 h of cold storage. Some grafts were subjected to gaseous persufflation with carbon monoxide (CO, dissolved in nitrogen) during static cold storage at a concentration of 50 ppm or 250 ppm. Graft viability was assessed thereafter upon warm reperfusion in vitro.

Results

CO-persufflation significantly reduced cellular enzyme loss (maximal at 50 ppm) and functional recovery (bile production and energy charge) upon reperfusion by about 50%. The effect was associated with a reduction of free radical-induced lipid peroxidation, lower vascular perfusion resistance, and improved mitochondrial ultrastructure.

Conclusion

Viability of cold stored liver grafts can be notably augmented by gaseous ex vivo application of low dose CO to the isolated organ.  相似文献   

5.

Objective

After analysing the effectiveness in the reduction in the incidence of functional impairment and a higher probability of returning home between elderly patients hospitalised due to an acute medical illness cared for in acute geriatric units (AGU) compared to conventional care units, we propose to assess the efficiency of this care.

Material and methods

A systematic review and meta-analysis was made of controlled studies (randomised, no randomised and case-control) that compared care in UGA with care in conventional hospital units of patients of 65 years and over with an acute medical illness. Studies on administrative data bases, those that evaluated care of a single disease, and those that assessed units with care in the acute and sub-acute phase were excluded. A literature review was performed on articles published up to 31st of August 2008 in Medline, Embase, Cochrane Library, and references of systematic reviews and reviewed articles. The selection of the studies and the extraction of data on the hospital stay and care costs was made independently by two different researchers.

Results

A total of 11 studies were included, of which 5 were randomised, 4 were non-randomised, and 2 case control, all of them providing data on hospital stay, with 7 of them providing data on hospital costs (4 clinical trials, 2 non-randomised and 1 case-control). The overall analysis of all the studies showed that those admitted to UGA had a statistically significant reduction in hospital length of stay compared to the elderly hospitalised in conventional units (mean difference -1.01 days; 95% CI, -1.66 to -0.36) and hospital care costs (mean difference of -330 US dollars; 95% CI, -540 to -120).

Conclusions

Care in AGU is more efficient than that provided in conventional units, since, as well as achieving a reduction in the incidence of functional impairment at discharge and increasing the probability of returning home, they reduce mean hospital stay and the hospital care costs.  相似文献   

6.
7.

Objectives

Evaluate the effect of diet, physical exercise, and a daily oral intake of a soy isoflavones extract (Fisiogen®) contained 200 mg of Glycine max, which corresponded to 80 mg of isoflavone (60.8 mg of genistein, 16 mg of daidzein and 3.2 mg of glicitein) on leptin and other adipokines plasma levels in healthy obese postmenopausal women.

Methods

A multicentric randomized longitudinal prospective cohort study was conducted in a sample of 87 healthy obese postmenopausal women. Patients were randomly assigned to a 1200 kcal diet and exercise group (control group) or a group of 1200 kcal diet, exercise, and daily oral intake of daily oral intake of a soy isoflavones extract (Fisiogen®) contained 200 mg of Glycine max, which corresponded to 80 mg of isoflavone (60.8 mg of genistein, 16 mg of daidzein and 3.2 mg of glicitein) (soy isoflavones group) along 6 months. Main outcome measures were: anthropometric measures, body composition, leptin, adiponectin, TNF-alpha, homocysteine, C-reactive protein, glucose, insulin, lipid profile and oestradiol serum levels, Kupperman index and Cervantes Scale.

Results

Mean serum leptin and TNF-alpha levels declined after 6 months in both groups of the study, but only women in the soy isoflavones group showed a significant increase of mean serum levels of adiponectin.

Conclusions

Diet, physical exercise and daily oral intake of a soy isoflavones extract (Fisiogen®) contained 200 mg of Glycine max, which corresponded to 80 mg of isoflavone (60.8 mg of genistein, 16 mg of daidzein and 3.2 mg of glicitein) have a beneficial effect on serum leptin, adiponectin and TNF-α in healthy obese postmenopausal women after 6 months of treatment.  相似文献   

8.

Background

There is no universally accepted and effective prophylaxis of migraine headache episodes. Thus we aimed to investigate the effects of Lippia alba (Mill.) N. E. Brown, an herb with many effects on central nervous system, on pain frequency and intensity of migraine patients.

Methods

Patients were enrolled in a prospective, phase 2, non-controlled cohort study to orally receive hydro-alcoholic extract of L. alba leaves. Headache intensity and frequency of episodes were recorded before and after 30-60 days of treatment. We also studied the chemical composition of its essential oil by gas chromatography-mass spectrometry.

Results

We described for the first time a particular L. alba chemotype with geranial and carvenone as major compounds. With treatment, both frequency and intensity of pain episodes significantly decreased from baseline to first reassessment date. More than 80% of patients experienced a minimum 50% reduction on pain intensity and frequency. No side effects were reported.

Conclusions

Treatment with a geranial plus carvenone chemotype of L. alba hydro-alcoholic extract is a cheap, widely available, highly effective therapy to reduce both the intensity and the frequency of headache episodes of migraine patients with no side effects.  相似文献   

9.

Introduction

Cryotherapy has been largely used in the past for palliation of unresectable liver tumors, but high local recurrence rates and peculiar systemic complications have determined its progressive abandonment. This review analyzes the histological changes produced to provide the basis for the local recurrences.

Materials and methods

A detailed literature search was performed on studies focusing on liver cryotherapy. Included were only those that described the histological characteristics in detail.

Results

A total of 22 studies were found, one clinical and the others in-vivo animal studies. Similar to other ablative techniques, cryotherapy produces a lesion which is composed by a central zone of coagulative necrosis surrounded with a transitional inflammatory zone. The lesion’s dimensions and morphology are influenced by numerous factors including the probe temperature, diameter, the duration of freezing time, fast cooling rate, slow thawing rate, the number of freezing cycles and the inflow occlusion (Pringle maneuver). The temporal evolution is consistent across studies and leads to a progressive inflammatory invasion of the necrosis with definitive fibrotic substitution.

Conclusions

Lesions obtained after cryotherapy seem similar and behave as those obtained after other techniques of liver ablation. However, controversial areas still exist and include the optimum number of freeze thaw cycles, the place of inflow occlusion, the potential corrupting effects of intra-lesional or proximal blood vessels on ablation morphology. The influence of these factors on the local recurrences are still not fully understood.  相似文献   

10.

Background

Drug resistant tuberculosis (TB) is a growing concern worldwide. Early detection of multidrug-resistant Mycobacterium tuberculosis is of primary importance for both patient management and infection control. Optimal method for identifying drug-resistant M. tuberculosis in a timely and affordable way in resource-limited settings is not yet available.

Aim

This study evaluated; nitrate reductase assay (NRA), resazurin microtiter assay (REMA) and microscopic observation drug susceptibility assay (MODS) against the conventional 1% proportion method (PM) for the detection of resistance to first line antitubercular drugs, in M. tuberculosis clinical isolates.

Methods

A total of one hundred and five clinical isolates of M. tuberculosis; 50 pan sensitive and 55 pan resistant were tested with NRA, REMA and MODS. The 1% proportion method on Lowenstein-Jensen medium was used as reference test.

Results

Of all three methods which were tested NRA was found to be most sensitive and specific. Sensitivity for rifampicin resistance detection was 100%, 94.55% and 92.73% by NRA, REMA and MODS respectively. NRA and REMA were found to be 100% specific, while the MODS was 98% specific for detection of rifampicin resistance. Test results with all these methods were obtained within 8-14 days.

Conclusion

Rapid non-conventional and inexpensive methods may serve as a replacement for 1% proportion method in resource limited settings.  相似文献   

11.
12.
Vilaça P  Rocha I  Rocha M 《Bio Systems》2011,103(3):435-441

Background and scope

Recently, a number of methods and tools have been proposed to allow the use of genome-scale metabolic models for the phenotype simulation and optimization of microbial strains, within the field of Metabolic Engineering (ME). One of the limitations of most of these algorithms and tools is the fact that only metabolic information is taken into account, disregarding knowledge on regulatory events.

Implementation and performances

This work proposes a novel software tool that implements methods for the phenotype simulation and optimization of microbial strains using integrated models, encompassing both metabolic and regulatory information. This tool is developed as a plug-in that runs over OptFlux, a computational platform that aims to be a reference tool for the ME community.

Availability

The plug-in is made available in the OptFlux web site (www.optflux.org) together with examples and documentation.  相似文献   

13.
Chronic Obstructive Pulmonary Disease (COPD) is a progressive disease with dyspnoea perception as a main symptom. In severe stages, dyspnoea can constitute a risk factor for depression, anxiety and somatization disorders.

Objective

The objective was to evaluate the presence of these psychopathologies based on dyspnoea and severity stages in patients with COPD.

Materials and methods

Patients (n=51) were evaluated by means of the Hospital Anxiety and Depression Scale, the dyspnoea scale (MRC), the General Health Questionnaire (GHQ-28) and spirometric criteria.

Results

The increase in dyspnoea level and disease severity lead to a progressive worsening of anxiety, depressive and somatic symptoms with clinical relevance (P<0.05). There was a significant correlation between those parameters (P<0.05).

Conclusions

The early detection and treatment of these psychopathologies associated with dyspnoea and progression of the disease must be taken into account in this complex pathology.  相似文献   

14.

Background

It is now evident that inflammation after vascular injury has significant impact on the restenosis after revascularization procedures such as angioplasty, stenting, and bypass grafting. However, the mechanisms that regulate inflammation and repair after vascular injury are incompletely understood. Here, we report that vascular injury-mediated cytokine expression, reactive oxygen species (ROS) production, as well as subsequent neointimal formation requires Toll-like receptor-2 (TLR-2) mediated signaling pathway in vivo.

Methods and results

Vascular injury was induced by cuff-placement around the femoral artery in non-transgenic littermates (NLC) and TLR-2 knockout (TLR-2KO) mice. After cuff-placement in NLC mice, expression of TLR-2 was significantly increased in both smooth muscle medial layer and adventitia. Interestingly, we found that inflammatory genes expression such as tumor necrosis factor-α, interleukin-1β (IL-1β), IL-6, and monocyte chemoattractant protein-1 were markedly decreased in TLR-2KO mice compared with NLC mice. In addition, ROS production after vascular injury was attenuated in TLR-2KO mice compared with NLC mice. Since we observed the significant role of endogenous TLR-2 activation in regulating inflammatory responses and ROS production after vascular injury, we determined whether inhibition of endogenous TLR-2 activation can inhibit neointimal proliferation after vascular injury. Neointimal hyperplasia was markedly suppressed in TLR-2KO mice compared with WT mice at both 2 and 4 weeks after vascular injury.

Conclusions

These findings suggested that endogenous TLR-2 activation might play a central role in the regulation of vascular inflammation as well as subsequent neointimal formation in injured vessels.  相似文献   

15.
Yadav D  Chandra R  Saxena R  Agarwal D  Agarwal M  Ghosh T  Agrawal D 《Gene》2011,487(2):166-169

Background

Difference in the capacity of xenobiotic metabolising enzymes might be an important factor in genetic susceptibility to cancer.

Methods

A case control study involving forty one gastric cancer patients and one hundred and thirty controls was carried out to determine the frequency of GSTM1 and GSTT1 null genotypes. The frequency of GSTM1 and GSTT1 null genotype was observed by carrying out multiplex PCR.

Results

There was no difference in the frequencies of the GSTM1 and GSTT1 null and the combined GSTM1 and GSTT1 null genotype between patients and control.

Conclusions

Our data suggest that GSTM1 and GSTT1 status may not influence the risk of developing gastric cancer.  相似文献   

16.

Background

It is well-known that tumor exerts nonmetastatic systemic effect on organism caused the development of paraneoplastic syndrome (PNS). Recent findings point to relationships between development of PNS and tumor-derived vascular endothelial growth factor (VEGF).

Aim

Comparative study of PNS manifestations in mice with transplanted two variants of Lewis lung carcinoma with different angiogenic potential.

Methods

Plasma VEGF level was determined by immunoenzyme method, hematological indices were estimated with the use of hematological analyzer, the weight and cellularity of spleen and thymus were registered and histological analysis of tissue section of these organs was performed.

Results

Manifestations of anemia, extramedullary hemopoiesis and tumor-associated inflammatory disease was observed in animals with high angiogenic LLC/R9 variant and was not registered in low angiogenic LLC. The emergence of PNS symptoms correlated with elevated level of circulating VEGF at the early stages of LLC/R9 growth.

Conclusion

Manifestation of the paraneoplastic hematological syndrome most likely is conditioned on the ability of cancer cell to secrete VEGF in a high rate.  相似文献   

17.

Objective

To evaluate the in vitro effects of different concentrations of ivermectin and/or artemether on Fasciolagigantica worms and to study the parasitological changes and tegumental alterations using scanning electron microscopy (SEM).

Methods

Fasciola gigantica worms were incubated in vitro for 24 and 48 h with three concentrations of either ivermectin or artemether (10, 20 and 50 μg/ml) or both in half concentration of either (5, 10 and 25 μg/ml).

Results

Exposure of Fasciola worms to 25 + 25 μg/ml of combined drug regimens or to 50 μg/ml of either ivermectin or artemether for 48 h led to 100%, 41.7% and 75% worm killing which were accompanied by a significant reduction in egg laying capacity and significant increase in dead eggs maximally recorded in combined drug regimens. SEM of the flukes incubated for 48 h with combined drug regimens showed maximal tegumental disruption with swelling of the worm body, roughness, blebbing, sloughing and complete loss of spines. Disruption to the tegument of the flukes induced by artemether was more than that of ivermectin.

Conclusions

Artemether alone or combined with ivermectin in half doses had potent fasciocidal activities. Besides, half doses of combined drug regimens had higher ovicidal effects than each drug alone. In vivo studies are recommended to explore the efficacy of combined regimens against Fasciola infection.  相似文献   

18.

Objective

To determine the signaling pathways and components involved in insulin-mediated regulation of Acyl-CoA: cholesterol acyltransferase1 (ACAT1).

Methods

THP-1 cells were cultured in RPMI 1640 medium and were induced into macrophages in the presence of 160 nM phorbol 12-myristate 13-acetate (PMA). Before insulin was added in, macrophages were preincubated with the inhibitors of the insulin signaling pathway, including wortmannin, phosphatidylinositol 3-kinase (PI3 K) inhibitor; PD98059, extracellular signal-regulated kinase (ERK) inhibitor; SB203580, p38 mitogen-activated protein kinase (p38MAPK) inhibitor; SP600125, c-Jun N-terminal kinase (JNK) inhibitor and U73122, phospholipase C-γ (PLC-γ) inhibitor. ACAT1 mRNA and protein expression level in macrophages were determined by real-time quantitative polymerase chain reaction and western blotting, respectively.

Results

Real-time quantitative polymerase chain reaction and western blotting demonstrated that PD98059, SB203580 or SP600125 down-regulated the expression of ACAT1 in a dose-dependent manner. However, no obvious alteration was found in wortmannin and U73122 groups.

Conclusion

These results suggest that the ERK, p38MAPK and JNK signaling pathways may be involved in insulin-mediated regulation of ACAT1, but no PI3K and PLC-γ signaling pathways were involved in the present study.  相似文献   

19.

Background

Chronic hepatitis B (CHB) is a vaccine preventable disease of global public health importance. The prevalence of CHB in New Zealand's Tongan population is over 10%, a level consistent with endemic infection, which contrasts to the low overall New Zealand prevalence (<0.5%). Despite the introduction of infant vaccination in 1988, coverage among Tongan children is estimated to be only 53%.

Aims

To estimate the population benefit of additional public health control measures besides ‘business as usual’ infant vaccination for hepatitis B in high prevalence populations.

Methods

A mathematical model of hepatitis B virus (HBV) transmission was used to predict future CHB prevalence in the New Zealand Tongan population under different infection control strategies.

Results

Prevalence of CHB is predicted to plateau at 2% in the New Zealand Tongan population if coverage remains at current levels, which are therefore insufficient to achieve long-term elimination of HBV. The critical proportion of immunisation coverage for elimination of the virus is estimated to be 73%. The effect of screening for HBV carriage and early disease management was unable to be quantified, but is likely to reduce the population burden of HBV infection and thus contribute to accelerating elimination.

Conclusions and recommendations

Mathematical models are a useful tool to forecast the future burden of CHB under a range of control strategy scenarios in high prevalence populations. Serosurveillance and targeted vaccination has similarly arrested HBV transmission in time-series prevalence studies from Taiwan and Alaska. Such a policy may demonstrate similar efficacy in New Zealand ethnic groups with endemic HBV infection.  相似文献   

20.

Background

The neurotrophin NGF receptors trkA and p75NTR are expressed in the central and peripheral nervous system as well as in non-neuronal tissues; originally described to localize to the plasma membrane, recent studies have suggested other intracellular localizations for both NGF receptors.

Scope of review

In order to determine whether NGF receptors localize to the mitochondrial compartment mitochondria isolated from human kidney, rat tissues and a human podocyte as cell line before and after differentiation were used.

Major conclusions

Our results demonstrate that NGF receptors are localized in the mitochondrial compartment of undifferentiated human podocytes and in all tissues analyzed including rat central nervous system. In mitochondria p75NTR, but not trkA, co-immunoprecipitates with the adenine nucleotide translocator (ANT) and the phosphodiesterase 4 isoform A5 (PDE4A5). Moreover, NGF, via trkA, protects isolated mitochondria of rat brain cortex from mitochondrial permeability transition induced by Ca2+.

General significance

Although NGF receptors have been described as mainly citoplasmatic so far, we proved evidence of their expression at the mitochondrial level and their interaction with specific proteins. Our results demonstrating the expression of NGF receptors in the mitochondria provide new insights into the role of NGF at subcellular level, in different areas of the organism, including CNS.  相似文献   

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